New  York 

SUBWAY 
VENTILATION 


HISTORY 

AND 

REMEDY 


i£x  Safaris 


SEYMOUR  DURST 


When  you  leave,  please  leave  this  book 

Because  it  has  been  said 
"Ever'thing  comes  t'  him  who  waits 

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Avery  Architectural  and  Fine  Arts  Library 
Gift  of  Seymour  B.  Durst  Old  York  Library 


NEW  YORK 
SUBWAY  VENTILATION 

(ILLUSTRATED  BY  DIAGRAMS) 


By 

JAMES  G.  DUDLEY,  A.  B. 

CONSULTING  ENGINEER 

NEW  YORK 


PART  I 

HISTORY 

(Pages  1-24) 


PART  II 

REMEDY 

(Pages  25-40) 


September  I,  191 5 


r 


CLASSES 


AA 


Copyrighted  1915 

BY 


JAMES  G.  DUDLEY 


Consulting  Engineer 

50  Church  St. 
New  York 


Press  of 
JOHN  C.  RANKIN  CO. 
54&56  DeySt.,  N.  Y. 


\ 


PART  I. 


HISTORY 


MEMO  FROM  - 

E.  V.  HALBMEIER 

A  very  trifling  addition  to  your 
collection,    with   the  regards  of 

EVH 


Present  "Piston"  Ventilation 


PART  L 


HISTORY 

Survey 

The  diagrams  accompanying  this  paper  naturally  do  not  and  need 
not  show  anything  other  than  the  merest  skeleton  of  the  construction 
as  it  exists,  or  as  it  is  planned  to  be  made,  nor  will  the  attempt  be 
made  to  prove  all  the  statements  herein  by  means  of  statistics  as  dry 
as  the  very  dust  in  the  subway,  nor  bulwark  the  technical  contentions 
with  an  array  of  unnecessary  data,  as  to  volumes,  velocities,  temper- 
atures, etc.,  since,  naturally,  access  has  not  been  given  to  the  figures 
which  are  possibly  buried  in  the  archives  of  the  engineers  who  designed 
the  subway.  However,  it  is  a  fact  that  within  a  fortnight  after  the 
first  subway  was  opened,  on  October  27th,  1904.  the  author  made  a 
special  trip  through  it  as  it  then  existed  from  end  to  end  with  the  sole 
purpose  of  studying  the  ventilation,  or  lack  of  it.  having  in  mind  the 
possibility  of  being  able  to  make  suggestions  which  might  be  of  service. 
From  that  day  to  this  further  studies  have  been  made  and  quite  a  large 
amount  of  data,  clippings,  etc..  in  regard  to  the  ventilation  of  the  old 
subway  and  of  other  subways  and  tunnels,  have  been  collected,  there- 
fore, when  statements  are  made  which  may  seem  dogmatic  it  is  to  be 
noted  that  they  are  made  after  mature  deliberation  and  exhaustive 
study  into  the  question  viewed  from  probably  every  possible  angle. 
In  like  manner  the  attempt  will  not  be  made  to  go  into  the  many  tech- 
nical sides  of  the  broad  subject  of  ventilation  covering  as  it  does  a  field 
which  is  growing  wider  every  day  owing  to  research  by  engineers, 
sanitarians  and  hygienists  of  eminence,  who  are  attacking  the  ques- 
tion of  what  constitutes  good  and  bad  ventilation  with  the  most  modern 
weapons  of  science,  and.  curiously,  are  overturning  many  theories  here- 
tofore well  accepted  upon  this  subject.  It  should  be  enough  for  the 
purpose  of  this  memorandum  to  assume  it  as  taken  for  granted  that, 
from  the  standpoint  of  hygiene,  efficiency,  safety,  comfort  and  even 
the  production  of  profits,  it  is  not  only  a  desirable  thing  to  have  the 
subways  well  ventilated,  but  it  has  at  last  come  to  be  a  compelling  neces- 
sity. In  defence  of  science  and  modern  engineering,  it  may  be  said 
that  in  those  circles  at  least  there  never  has  been  any  question  that  the 
subway  was  not  ventilated,  nor  that  it  could  not  be  ventilated,  hence 
it  is  well  worth  most  serious  consideration  to  find  why  it  is  that  the  sub- 
ways have  not  been  properly  ventilated,  and  why  the  proposed  plans  for 
those  projected  are  so  obviously  inadequate. 

Possibly  this  introduction  may  seem  a  trifle  irrelevant  but  in  view 
of  the  fact  that  now.  after  ten  years  of  use  and  experiment,  proper  venti- 


6  Subway  Ventilation 

lation  is  not  incorporated  in  the  design  or  operation  of  the  subway, 
it  will  readily  be  conceded  that  we  must  get  a  proper  perspective  before 
attempting  to  pass  upon  the  strictly  engineering  and  structural  features 
of  the  plans  which  have  been  tried,  or  those  which  are  proposed  to  be 
tried. 


Diagram  A 

Original  Design 

Reverting  now  to  the  very  inception  of  the  first  subway,  attention 
is  called  to  the  Diagram  A  which  shows  the  subway  as  it  was  origi- 
nally designed  and  built  and  put  into  commission  on  Oct.  27th,  1904. 
It  may  be  recalled  that  this  was  done  under  the  Rapid  Transit  Rail- 
road Commission  and  that  it  was  not  until  some  years  afterwards  that 
the  present  Public  Service  Commission  took  over  the  rights  and  duties 
which  were  covered  originally  by  the  Rapid  Transit  Railroad  Com- 
mission. Xo  sooner  had  the  subway  been  officially  opened  to  the  public 
than  strong  criticism  developed  of  the  ventilation  or  rather  lack  of 
ventilation  since,  strange  as  it  may  seem,  no  provision  therefor  had  been 
made  by  those  responsible  for  the  design. 

In  passing  it  may  be  said,  as  far  as  possible,  there  will  not  be  sub- 
mitted herein  mere  opinions,  but  when  such  statements  are  made,  they 
are  in  reality  quoted  from  official  documents  although  in  order  to  develop 
this  subject  in  a  logical  and  historical  fashion,  the  authorities  for  the 
statements  may  not  come  out  until  well  along  in  this  paper. 

Technical  Investigations 

As  evidence  that  this  public  criticism  was  immediate  and  spon- 
taneous, it  is  sufficient  to  say  that  the  author's  studies  were  begun 
within  less  than  a  month  of  the  opening  of  the  subway  and  because  of 


History  and  Remedy 


7 


this  criticism.  Incidently,  because  of  the  actual  conditions,  the  Rapid 
Transit  Commission  and  its  Chief  Engineer,  who  at  that  time  was 
Mr.  George  S.  Rice,  immediately  began  an  investigation  the  results  of 
which  are  embodied  in  the  formal  report  of  the  Hoard  of  Rapid  Transil 
Railroad  Commission  for  the  City  of  New  York  for  the  year  ending 
Dec.  31st,  1906,  and  published  on  or  about  Jan.  1st.  1907.  copy  of  which 
is  available  for  inspection  by  anyone  in  the  Library  of  the  present  Public 
Service  Commission  at  the  Tribune  Building.  In  this  report  on  page  81 
this  statement  appears:  "The  first  advent  of  warm  weather  showed 
rather  an  unexpected  condition  of  the  atmosphere  of  the  subway." 
Here  we  see  that  the  designers  proceed  upon  the  false  assumption  that 
the  subway  would  ventilate  itself,  or,  in  other  words,  that  the  agita- 
tion of  the  air  by  train  movement  and  any  excess  heat  of  the  air  within 
the  subway  would  be  effectively  provided  for  by  egress  and  ingress  of 
air  through  the  passenger  stations  which  perforated  the  tube  at  more 
or  less  frequent  intervals. 

In  justice  to  the  designers  it  might  be  noted  in  passing,  that,  at 
that  time,  subways  were  somewhat  of  a  novelty  and  this  one  being  the 
first  in  New  York,  it  might  have  been  assumed  that  the  conditions  were 
so  peculiar  that  results  would  obtain  here  which  did  not  obtain  in  sub- 
ways of  London,  Paris  and  Boston.  On  the  other  hand  it  is  quite  as 
evident  that  engineers,  expert  in  ventilating,  were  not  called  into  con- 
sultation. 

Technical  Reports 

As  a  result  of  the  investigation  made  in  the  Spring  of  1905  by  the 
Commission,  it  was  decided  to  call  in  one  of  the  foremost  sanitarians 
of  this  country,  if  not  of  the  World.  Accordingly  Prof.  Geo.  A.  Soper 
of  Rensselaer  Polytechnic  Institute  of  Troy  was  retained  by  the  Com- 
mission to  make  a  scientific  report  upon  the  actual  conditions  of  the 
subway  relative  to  the  health  of  the  employees  and  the  travelling  public. 
In  addition  to  this,  the  Chief  Engineer  of  the  Commission  conducted 
certain  practical  investigations  with  his  own  staff,  and  also  made  a 
report  to  the  Commission  already  referred  to.  It  is  very  evident  from 
a  reading  of  these  reports  that  Dr.  Soper  confined  his  investigations 
strictly  to  the  scientific  aspects  of  the  matter  and  left  the  practical 
details  fully  in  the  hands  of  the  Commission's  Chief  Engineer,  Mr. 
Geo.  S.  Rice,  all  of  which  Dr.  Soper  takes  some  pains  to  make  clear  in 
his  report. 

It  is  now  necessary  to  anticipate  the  findings  of  these  reports  in 
order  to  make  clear  the  physical  conditions  governing  this  matter  of 
ventilation  or  lack  of  ventilation.  As  it  was  later  developed,  more  than 
85°^  of  all  the  energy  generated  at  the  power  stations  of  the  subway  is 
dissipated  in  the  form  of  heat  inside  the  subway  itself  in  the  stopping 


8 


Subway  Ventilation 


of  the  trains,  in  the  agitation  of  the  air,  in  the  action  of  the  friction  of 
the  brake  shoes  upon  the  wheels,  of  the  pounding  of  the  wheels  upon 
the  rails  and  other  such  mechanical  evidences  of  heat,  all  of  which  are 
supplemented  by  the  heat  of  the  electric  lights  and  the  body  heat  from 
the  passengers,  etc.  etc.  The  result  of  all  this  excess  heat  produces  a 
condition  which,  in  warm  weather  at  least,  is  considered  by  the  public 
at  large  as  "most  uncomfortable.' ' 

First  A  Iterations 

By  reference  then  to  Diagram  A  it  will  be  noted  that  the  subway 
had  been  opened  for  probably  six  or  eight  months  before  any  alteration 
or  addition  was  made  to  remedy  defective  ventilation. 

While  Prof.  Soper  was  conducting  his  investigations,  Chief  Engineer 
Rice  was  beginning  to  make  certain  alterations  which  it  was  assumed 
would  help,  if  they  did  not  entirely  remedy  the  evils  complained  of. 
From  a  construction  standpoint  then,  the  subway  consisted  of  a  continu- 
ous underground  tube  with  a  number  of  perforations  in  its  envelope 
between  the  two  terminals  which  perforations  were  the  passenger 
stations,  nor  were  there  any  other  vent  openings  provided.  We  now 
find  that  the  engineers  proceeded  on  the  assumption  that  by  punching 
additional  holes  preferably  in  the  covering  of  the  subway,  the  excess 
heat  would  escape  to  the  atmosphere.  This  could  only  take  place  if 
such  a  perforation  is  connected  to  a  fan  or  chimney  which  will  produce 
a  draft  and  as  this  was  not  done  naturally  no  benefit  followed.  In 
addition  to  this,  the  Chief  Engineer  not  only  suggested  refrigeration  of 
the  air,  but  actually  made  quite  an  extensive  attempt  to  do  this  at  the 
Brooklyn  Bridge  station.  Undoubtedly,  many  have  noticed  the 
fan  chamber  and  ducts,  and  other  evidences  of  this  so-called  refrig- 
erating scheme,  but  may  not  have  known  what  it  was  intended  for. 
The  method  followed  consisted  of  driving  a  well  to  a  considerable 
depth  from  which  relatively  cold  water  was  obtained.  This  being 
pumped  to  the  surface  was  sprayed  through  nozzles  and  air  from  the 
station  was  drawn  in  by  fans  and  was  forced  through  this  mist  of  water 
and  thereby  somewhat  cooled,  whereupon  the  air  was  forced  out  through 
ducts  to  lower  the  rising  temperature  of  the  waiting  passengers  at  the 
stations.  When  one  realizes  that  in  the  old  subway  from  the  Brooklyn 
Bridge  to  Columbus  Circle  a  length  of  4J/2  miles,  there  is  something 
like  27,000,000  cubic  feet  of  air  to  be  cooled  by  an  amount  equal  to  85% 
of  all  the  heat  energy  generated  at  the  central  stations,  one  does  not  have 
to  be  a  scientist  or  an  engineer  to  see  the  utter  futility  of  such  a  scheme 
and  the  very  statement  of  the  attempt  is  a  sufficient  criticism  of  it. 

This  cooling  plant  was  completed  and  put  into  commission  on 
Aug.  29th,  1906  (see  pages  197  to  203  of  the  report).  Prof.  Soper's 
investigations  cover  a  period  between  July  1st,  1905,  and  Dec.  31st, 


History  and  Hk.mf.dv 


9 


1905.  Although  he  made  a  preliminary  report  on  Oct.  19th,  1905,  the 
main  findings  were  not  available  for  public  inspection  prior  to  Jan. 
1st,  1907.  Many  excerpts  have  been  made  from  this  report  giving  the 
essentials  of  the  investigation  which  can  readily  be  verified  in  substan- 
tiation of  any  statement  herein  made.  Accompanying  the  report  to 
the  Rapid  Transit  Commission  by  Prof.  Soper  was  a  report  from  Chief 
Engineer  Rice,  which  contains  amongst  other  things  the  following 
recommendations  and  suggestions  in  addition  to  the  cutting  of  the  open- 
ings already  spoken  of  and  the  installation  of  the  so-called  refrigerating 
plant.  On  page  194  of  the  report,  it  was  recommended  that  there 
should  be  a  complete  renewal  of  the  contents  of  the  subway  every 
half  hour,  which  means,  as  will  be  noted,  the  removal  of  54,000,000 
cubic  feet  of  air  per  hour.  These  are  very  large  figures,  but  the  subject 
and  the  subway  are  likewise  large  propositions,  and  consequently  call 
for  large  terms.  That  this  was  a  very  conservative  recommendation 
is  clear  when  it  is  learned  that  in  good  ventilating  practice  the  cubic 
contents  of  a  building,  say  of  a  hospital  or  a  theatre  occupied  by  large 
numbers  of  people,  are  in  many  cities,  required  by  law  to  be  changed 
from  four  to  six  times  per  hour. 

Installation  of  Fans 

It  quickly  became  obvious  to  the  engineers  that  the  cutting  of 
holes  in  the  roof  of  the  subway  was  not  going  to  effect  a  real  change  of 
the  cubic  contents  of  the  subway  at  all,  however  it  might  effect  it  in 
spots,  hence  there  were  installed  at  various  points  in  connection  with 
these  roof  openings  some  25  blowers  ranging  from  five  to  seven  feet 
in  diameter  driven  by  electric  motors  of  15  to  30  H.P.  each  which  com- 
bined were  capable  of  exhausting  from  the  subway  fully  1,000,000  cubic 
feet  of  air  per  minute.  The  application  of  a  little  arithmetic  will  show 
that  these  fans  would  then  exhaust  from  the  subway  an  amount  of  air 
every  hour  in  excess  of  the  recommendations  of  the  engineers,  or  in 
other  words,  60,000,000  cubic  feet  as  against  the  required  54,000,000 
feet.  Even  assuming  that  these  blowers  were  operated  at  all  times  at 
their  full  capacity,  the  question  naturally  arises,  what  results  were 
accomplished  thereby?  Chief  Engineer  Rice  on  March  22d,  1906, 
says  in  his  report,  on  page  82  that  "  a  large  part  of  the  construction 
\vas  completed  in  the  Summer  (1905)  with  the  result  that  the  subway 
was  noticeably  cooler.  The  refrigeration  experiments  were  also  car- 
ried on  with  satisfactory  results. "  If  a  straw  vote  were  taken  from  the 
passengers  in  the  subway  during  the  Summer  of  1915,  it  may  very  well 
be  doubted  that  a  very  large  majority  would  even  at  this  date  agree 
with  Chief  Engineer  Rice  in  his  findings. 

In  view  of  the  recent  accident  and  fire  in  the  subway,  it  is  most 
significant  to  note  that  the  Chief  Engineer  in  his  report  on  page  196  fore- 


10 


Subway  Ventilation 


saw  the  possibility  and  dangers  of  smoke  and  recommended  blowers  for 
meeting  such  an  emergency  and  further,  on  page  200,  a  still  wiser  recom- 
mendation was  made  that  a  separate  power  cable  and  emergency  ser- 
vice should  be  provided  for  driving  these  blowers  should  the  main  power 
circuit  be  put  out  of  commission. 

Prof.  Soper  s'  Conclusions 

Coming  now  to  the  report  of  Prof.  Soper,  and  without  referring 
to  hypertechnical  details,  the  whole  might  be  summed  up  in  his  "Digest 
of  Results"  in  the  following  which  appears  on  page  214  of  the  report: 
"For  the  main  part  the  air  analyzed  has  been  that  at  an  elevation  of 
18  inches  to  2  feet  above  the  pavement.  This  height  was  decided  on 
as  the  most  convenient  and  suitable  after  comparative  tests  of  the  air  at 
different  elevations.  But  few  samples  were  taken  of  the  air  of  the  cars, 
since  this  was  the  desire  of  your  Chief  Engineer"  meaning  George  S. 
Rice.  This  might  fairly  be  said  to  be  the  mouse  which  the  mountain 
brought  forth!  For,  in  the  name  of  common  sense,  it  may  be  asked 
why  a  few  specific  points,  at  a  few  specific  stations,  should  be  selected 
at  a  height  of  18  inches  or  2  feet  above  the  floor,  at  which  to  determine 
whether  the  subway  was  or  was  not  properly  ventilated;  and,  why  in 
the  name  of  engineering  and  science,  were  but  a  few  samples  taken  of 
the  air  of  the  cars;  and  why  was  it  the  Chief  Engineer's  desire  that  more 
should  not  be  taken?  One  may  ask  the  Rapid  Transit  Commission  and  its 
experts  whether  the  public  travel  "on  the  stations"  or  "in  the  cars?" 
Granting  that  the  public  do  use  the  stations,  it  is  but  for  a  very  small 
percentage  of  the  time  spent  within  the  subway,  hence  it  is  fundamental 
that  the  determination  of  ventilation,  or  lack  of  ventilation  should  be 
reached  by  an  analysis  of  the  air  within  the  cars  almost  to  the  exclu- 
sion of  the  air  at  any  other  point.  Accompanying  these  very  volumi- 
nous reports  will  be  found  drawings  Nos.  1  and  2  showing  plans  of  the 
ventilation  of  the  subway  between  the  Battery  and  96th  St.,  also  charts 
Nos.  3  and  4  showing  the  temperature  variations  within  the  subway;  also 
plans  of  Brooklyn  Bridge  cooling  plant.  Care  has  been  taken  to  bring 
out  the  essence  of  this  report  since  that  is  the  foundation  from  which  any 
investigation  should  start.  That  it  was  not  considered  of  small  impor- 
tance is  seen  in  the  fact  that  it  was  followed  in  1908  by  the  publication, 
through  John  Wiley,  of  a  book  entitled  "Air  and  Ventilation  in  Sub- 
ways" by  George  A.  Soper.  Ph.  D..  Member  of  American  Society  of 
Civil  Engineers,  Member  American  Chemical  Society,  Member  of 
Society  of  American  Bacteriologists,  Member  of  the  American  Public 
Health  Association. 

Supplementary  Changes 

It  will  be  noted  that  at  the  time  of  the  submission  of  these  reports, 
which  were  published  on  or  about  Jan.  1st,  1907,  the  subway  had  been 


History  and  Remedy 


11 


altered  from  the  construction  shown  in  Diagram  A  at  34  stations  and 
34  points  between  stations  to  that  shown  in  Diagram  B  which  illus- 
trates the  perforation  made  in  the  roof  of  the  subway  in  the  attempt 
to  permit  the  excess  heat  to  escape  by  natural  means.  Supplementing 
this  change  there  was  devised  the  scheme  shown  in  Diagram  C  consist- 
ing of  vent  chambers  between  stations  at  the  sides  of  the  subway.  This 
was  an  attempt  to  control  the  inflow  and  outflow  of  the  subway  air  by 
the  " piston-like"  action  of  the  trains  and  check  valves  or  louvres 
hinged  in  a  most  ingenious  and  elaborate  fashion  in  the  side  wall  of  the 
subway.  As  will  be  noted  from  these  vent  chambers  ducts  connected 
with  sidewalk  gratings,  the  idea  being  that  upon  the  approach  of  a 
train  the  air  would  be  compressed  in  the  neighborhood  of  these  chambers 
and  the  flaps  would  be  opened  and  the  air  would  be  expelled  through 
the  grating  as  is  the  case,  and  that  when  the  train  had  gone  by  the  air 
suction  created  thereby  would  pull  these  check  valves  closed  and  air 
would  be  drawn  into  the  subway  at  the  next  nearest  hole  which  would 
probably  be  at  the  station  immediately  behind  the  oncoming  train. 
See  title  page. 


In  theory  the  scheme  of  the  louvres  is  most  ingenious  and  desirable 
provided  that  the  trains  did  in  reality  act  as  pistons  within  a  cylinder, 
but  such  is  not,  and  cannot  be  the  case,  inasmuch  as  it  is  clear  that  a 
local  train  in  the  compartment  on  the  extreme  right  of  the  subway  and 
nearest  to  these  vent  chambers  would  practically  have  to  fill  all  four 


12 


Subway  Ventilation 


compartments  in  order  to  so  act.  Since  this  is  not  the  case  there  results 
simply  an  agitation  of  the  air  with  some  slight  and  casual  expulsion  of 
air  through  these  louvres  and  vent  chambers. 

Diagram  D  shows  the  so-called  refrigerating  plant  at  the  Brooklyn 
Bridge. 

Cost  of  Fan  Operation 

In  order  to  get  some  comprehension  of  the  initial,  and  operating 
cost  of  such  blowers,  which,  according  to  the  Chief  Engineer,  were 
operated  by  motors  ranging  from  15  to  30  H.P.,  it  will  be  seen  ^hat, 
assuming  an  average  of  20  H.P.  apiece,  500  H.P.  per  hour  would  have 
been  required  according  to  the  Chief  Engineer  for  removing  the  60,000,- 
000  cubic  feet  of  air  within  the  subway  between  the  Battery  and  96th 
St.  and  thereby  change  its  cubic  contents  once  every  half  hour.  A  very 
little  arithmetic  shows  that  this  would  amount  to  $120.00  for  every  24 
hours  of  continuous  fan  operation  on  the  assumption  of  a  cost  $.01  per 
H.P.  per  hour.    It  cannot  be  questioned  that  25  such  blowers  so  driven 


Diagram  C 


would  exhaust  from  the  subway  the  amount  of  air  specified,  but  especial 
attention  is  called  to  the  fact  that  this  does  not  by  any  manner  of 
means  insure  that  the  cubic  contents  of  the  subway  "from  the  Battery 
to  96th  St.,"  would  ever  be  changed  even  once  in  a  year — for  the  very 
obvious  reason  that  an  amount  of  air  exactly  equal  to  that  exhausted 
by  the  fans  must,  and  will,  flow  back  into  the  subway  through  the 
openings  nearest  to  the  fans  and  would,  unless  provision  be  made  there- 
for, result  in  short-circuiting  of  the  air  and  thereby  practically  defeat 
the  plan  and  only  partially  relieve  the  conditions  at  a  few  points. 


History  and  Remedy 


13 


Metallic  Dust 

The  "deposits"  on  the  floor  of  the  subway  in  Diagram  E  are 
diagrammatic  representations  of  one  of  the  very  interesting  facts  which 
was  developed  by  the  reports  referred  to,  namely:  "That  it  is  a  matter 
of  official  information  that  the  loss  of  weight  in  brake  shoes  has  amounted 
to  one  ton  per  mile  per  month."  The  iron  so  ground  up  into  powder 
and  so  deposited,  or  remaining  in  suspension  in  the  air  of  the  subway, 
probably  now  amounts  to  more  than  900  tons!  Obviously  this  metallic 
dust  either  remains  in  suspension  to  be  breathed  in  by  the  passengers 
or  is  too  heavy  and  falls  to  the  floor  of  the  subway  there  to  remain  until 
the  suction  of  the  train  sets  it  into  motion.  Either  of  these  assumptions 
is  another  strong  reason  for  frequent  and  positive  flushing  out  of  the 
entire  contents  of  the  subway. 

Suggested  Remedies 

Before  one  leaves  this  stage  of  the  investigation,  it  is  interesting 
to  note  that  on  Sept,  19,  1906,  Charles  S.  Churchill,  Member  of  the 
American  Society  of  Civil  Engineers,  submitted  a  paper  to  his  society 
upon  "The  Ventilation  of  Tunnels"  which  paper  was  discussed  by 
Reginald  P.  Bolton,  George  S.  Rice  and  the  author  himself.  In  this 
paper  distinct  issue  is  taken  with  the  methods  pursued,  or  not  pursued, 
in  the  attempt  to  ventilate  the  subway;  and  reference  is  made  to  the 
suggestions  of  Mr.  Churchill  in  1904  preceding  the  opening  of  the  sub- 
way, in  which  he  called  attention  to  the  absolute  necessity  of  employing 
mechanical  ventilation,  i.e.  fan  ventilation.  It  is  worthy  of  note  that 
it  was  in  this  discussion  that  Engineer  Rice  called  attention  to  the 
possibility  of  the  presence  of  smoke  in  the  subway  and  its  dangers, 
and  that  it  was  also  in  this  discussion  that  Mr.  Bolton  suggested  "agi- 
tators" within  the  cars — a  suggestion  which  obviously  cannot  add  one 
iota  to  the  ventilation  of  the  subway  but  merely  stirs  up  the  foul  and 
heated  air  within  the  cars  themselves.  In  this  discussion  it  was  also 
brought  out  that  the  air  in  the  Boston  subways  was  figured  to  be  renewed 
six  times  per  hour,  or  once  every  ten  minutes,  which,  if  duplicated  in 
the  New  York  subways,  would  unquestionably  result  in  excellent 
conditions. 

On  March  15th,  1906,  Prof.  Soper  read  a  paper  before  the  New  York 
Academy  of  Medicine  in  which  he  says,  in  conclusion,  "I  should  say 
that  I  think  the  subway  as  a  whole  is  sufficiently  ventilated  and  free 
from  conditions  injurious  to  health  except  as  to  presence  of  metallic 
dust,  lack  of  sanitarv  care,  and  conditions  inseparable  from  overcrowd- 
ing." 

The  Arnold  Investigation 

Leaving  now  the  subway  as  "ventilated"  by  Prof.  Soper  and  Chief 
Engineer  Rice,  we  pass  over  the  year  1907  to  Aug.  loth,  1908,  when,  as 


14 


Subway  Ventilation 


the  result  of  the  public's  disagreement  with  the  learned  gentleman 
above  quoted,  Bion  J.  Arnold,  the  great  electrical  engineer  and  trac- 
tion expert  of  Chicago  was  retained  by  the  Rapid  Transit  Railroad  Com- 
mission to  make  a  second  report  upon  the  ventilation  or  lack  of  venti- 
lation of  the  subway. 


This  report  is  also  available  to  any  investigator,  for  it  is  in  the 
Library  of  the  Public  Service  Commission  at  the  Tribune  Bldg.,  but 
the  essence  of  it  is  found  in  the  following  exact  transcripts:  On  page  1 
the  statement  is  made  that:  "when  the  subway  was  originally  built  no 
special  provision  was  made  for  the  disposal  of  the  accumulative  heat  or 
for  its  positive  ventilation. "  On  page  7  it  says:  "The  heat  of  the  sub- 
way comes  from  the  operation  of  the  trains  due  to  the  fact  that  about 
85%  of  the  electric  energy  produced  by  the  power  plant  which  operates 
the  road  is  dissipated  in  the  subway  in  the  form  of  heat.  The  amount 
of  heat  given  off  by  the  train  operation  in  24  hours  in  the  subway  between 
96th  St.  and  the  Brooklyn  Bridge  approximates  the  heat  liberated 
from  burning  directly  in  the  subway  two  tons  of  coal  at  each  of  the 
twenty  stations  in  this  section,  or  a  total  of  40  tons  during  the  24  hours. 
The  most  available  ways  for  reducing  the  temperature  of  the  air  in  the 
subway  are  as  follows:  1,  Refrigeration;  2,  Cooling  by  water;  3,  Block- 
ing the  automatic  louvres  open  and  providing  additional  openings;  4, 
Frequent  air  changes  by  means  of  a  centre  wall  and  train  movement. 
Now  the  opposite  train  movements  churn  and  whip  the  air  producing 
opposing  pressures  and  a  rotating  effect  of  the  air  about  the  train.  The 
result  is  that  most  of  the  air  has  no  definite  direction  of  travel  and 
remains  in  the  subway  instead  of  being  discharged  through  openings 


History  and  Remedy 


L5 


along  the  route.  Piston  ventilation  would  make  a  change  of  air  therein 
at  least  six  times  per  hour."  However,  on  page  12  of  his  report,  Mr. 
Arnold  suggests  that  "4  disk  fans  should  be  installed  at  each  station  at 
a  cost  of  not  over  $5,000.  per  station." 

Examining  the  different  recommendations  of  Mr.  Arnold  it  is  clear 
that  subway  construction  and  operation  would  practically  cease  if  it 
were  necessary  to  ventilate  them  by  means  of  actual  mechanical  "refrig- 
eration" predicated  upon  anything  known  to  science  today.  As  to  the 
second  recommendation  that  of  "cooling  the  air"  by  water  spray  as  was 
done  at  the  Brooklyn  Bridge,  enough  has  already  been  said  to  show  the 
futility  of  this  method.  The  third  suggestion,  to  "keep  open  the 
louvres"  and  cut  additional  gratings  in  the  sidewalks  and  elsewhere,  is 
equivalent  to  throwing  away  the  louvres  as  useless  and  resorting  to  the 
original  suggestion  of  Engineer  Rice  to  punch  more  holes  in  the  roof 
of  the  subway  and  let  the  agitation  of  the  trains  take  the  place  of  agita- 
tion for  better  ventilation  by  the  people  themselves.  The  fourth 
suggestion  of  building  within  the  subway  a  "division  wall"  between 
the  uptown  and  downtown  tracks  which,  to  quote  Mr.  Arnold,  "would 
result  in  a  change  of  the  air  in  the  subway  once  every  10  minutes," 
would  obviously  result  only  in  an  enormous  additional  cost  without 
accomplishing  anything  whatsoever  since,  to  be  effective,  the  piston 
would  have  to  be  as  wide  as  the  two  divisions  instead  of  one-half  as  wide 
as  is  the  case. 

The  fifth  suggestion  made  was  that  "disk  fans  be  installed  at  every 
station, "  but  just  how  this  was  to  change  the  entire  contents  of  the  sub- 


DlAGHAM  E 


L6 


Subway  Ventilation 


way  a  definite  number  of  times  per  hour  was  not  made  clear.  Hence 
we  can  fairly  dismiss  this  report  with  all  its  recommendations  as  again 
failing  utterly  to  accomplish  any  step  in  advance. 
Criticisms  Ignored 

From  1908  on  there  appears  to  have  been  no  further  attempts  to 
ventilate  the  subway,  as  far  as  official  documents  are  available  to  the 
public,  and  certainly  the  public  will  not  claim  that  any  change  in  the 
operating  conditions  have  been  noticed.  As  a  result  the  public  has 
suffered  and  from  time  to  time  voiced  its  complaints  with  no  noticeable 
benefit. 

About  the  time  of  the  settlement  of  the  involved  question  relating 
to  the  building  of  new  subways  and  extensions  of  the  old,  public  criti- 
cism became  so  acute  that  the  operators  of  the  subway,  the  Interborough 
Rapid  Transit  Co.,  did  install  in  the  cars  themselves,  the  "agitators," 
suggested  by  Mr.  Reginald  R.  Bolton  on  Sept.  19th,  1906 — only  throw- 
ing, literally  and  figuratively,  more  dust  in  the  eyes  of  the  people! 

V.  ntilation  of  New  Subways 

When  on  "  March  19th,  1913,  the  City  of  New  York  by  the  Public 
Service  Commission  for  the  First  District,  entered  into  separate  con- 
tracts with  the  Interborough  Rapid  Transit  Co.  and  the  N.  Y.  Municipal 
Railway  Corp.  for  the  construction,  equipment  and  operation  of  the 
Dual  system, "  the  public  again  lifted  up  its  voice  in  protest  upon  the 
subject  of  subway  ventilation. 

This  protest  first  took  shape  in  letters  to  the  newspapers,  editorials, 
comments,  etc.,  calling  attention  to  the  conditions  to  which  the  travel- 
ling public  seriously  object  and  demanded  from  the  designers  of  the 
subway  the  incorporation  of  a  real  remedy  in  the  new  subway. 

When  the  plans  of  the  proposed  Broadway  subway,  as  designed  by 
the  Rapid  Transit  Commission,  became  available  for  public  inspection, 
this  protest  took  a  definite  form.  Amongst  the  first  to  voice  an  organ- 
ized protest  was  the  Broadway  Association,  who  on  Oct.  24,  1913,  held 
a  public  meeting  at  the  Hotel  McAlpin  at  which  many  representative 
citizens  and  engineers  spoke  in  unqualified  condemnation  of  the  plans 
providing  for  ventilation  by  cutting  holes  in  the  sidewalks  along  the 
route  of  the  subway  and  adjacent  to  the  retail  stores.  Much  that  has 
already  been  presented  herein  was  brought  out  at  this  meeting  which 
resulted  in  the  appointment  of  a  special  committee  to  go  further  into  the 
matter  and  take  up  consideration  of  the  same  with  the  proper  authori- 
ties. 

The  method  at  that  time  proposed  by  the  Public  Service  Com- 
mission is  shown  in  Diagram  F  and  is  a  representation  of  the  typical 
vent  chambers  in  which  the  25  blowers  were  installed  according  to  the 
design  and  specifications  of  Chief  Engineer  Rice. 


History  and  Remedy 


17 


Diagram  F 


Before  leaving  Diagram  F  attention  is  called  to  the  extreme  lia- 
bility of  this  divisional  wall  complicating  the  operation  of  the  subway 
and  becoming  a  fresh  scource  of  danger  to  at  least  the  employees  who 
are  compelled  to  work  within  the  subway  on  foot. 

It  will  be  noted  that  this  plan  is  nothing  more  nor  less  than  an 
extension  and  elaboration  of  Diagram  E  and  the  construction  and 
scheme  provided  for  by  Mr.  G.  S.  Rice  back  in  1906,  and  that  again 
no  real  advance  is  made  since  there  is  omitted  entirely  any  control  of  the 
points  of  admission  of  the  air  drawn  in  by  the  fans  and  hence  there  must 
result  in  consequence  the  " short  circuit"  objection  to  which  the  scheme 
shown  in  Diagram  E  was  open.  In  addition  to  this,  the  holes  through 
which  these  fans  would  discharge  are  the  same  sidewalk  gratings  already 
referred  to,  but  to  which  the  Broadway  Association  so  rightfully  objects 
even  when  the  air  is  expelled  only  by  the  casual  "  piston-like"  action  of 
the  trains.  One  might  also  ask  how  much  more  will  they,  and  the 
public,  object  when  the  air  is  expelled  by  a  huge  blower  with  a  powerful 
motor  driving  it? 

For  its  own  guidance  and  protection  the  Broadway  Association 
had  retained  as  its  technical  adviser,  Mr.  Henry  G.  Opdycke,  Consult- 
ing Engineer,  who  presented  a  definite  alternative  scheme  as  depicted 
in  Diagram  G. 

It  is  now  in  order  to  critically  examine  each  of  these  plans  in  detail, 
for  inasmuch  as  they  are  the  outcome  of  more  than  ten  years  agitation 
upon  this  subject,  and  are  seriously  offered  by  engineers  of  undoubted 
ability  and  prominence  in  their  respective  fields,  they  are  entitled  to 
stand  or  fall  strictly  upon  their  merits. 


Subway  Ventilation 


Diagram  G 


Alternatives  Analyzed 

Referring  to  Diagram  F  it  is  evident  that  this  is  in  its  main  fea- 
tures only  an  elaboration  of  the  first  suggestion  of  Chief  Engineer 
Rice  with  the  actual  complications  of  those  suggestions,  as  they  were 
carried  out  on  the  old  subway  early  in  1906  save  and  except  that  it  was 
proposed  to  incorporate  into  the  subway  design  and  construction  a 
central  division  wall  suggested  by  Bion  J.  Arnold  in  his  report  of  1908. 
Detailed  analysis  has  already  been  made  of  the  results  which  would  or 
would  not  follow  from  the  construction  of  such  a  divisional  wall,  and  we 
have  seen  that  no  material  benefit  could  result.  It  now  develops  that 
this  divisional  wall  separating,  as  it  does,  the  uptown  tracks  from  the 
downtown  tracks  is  actually  designed  and  contracted  for  to  be  built 
with  a  multiplicity  of  openings  provided  for  therein  so  as  to  give  em- 
ployees ready  access  from  one  side  of  the  subway  to  the  other  not  only 
in  the  conduct  of  their  regular  work,  but  also  in  the  event  of  emergency 
for  themselves  and  passengers,  and  in  addition  to  permit  escape  from 
oncoming  trains.  These  openings  are  of  such  size  and  frequency,  viz 
2  feet  wide  by  7  feet  high  at  10  feet  centers,  that  the  divisional  wall  is 
little  less  than  a  huge  grating!  What  possible  service  it  could  perform 
in  even  the  contemplated  scheme  of  ventilating  the  subway  by  the 
" piston  action"  of  the  train  is  almost  beyond  comprehension! 

It  is  possible  to  get  some  idea  of  the  cost  involved  when  one  realizes 
that  this  divisional  wall  is  built  of  concrete  10  in.  thick  and  is  some  13 
ft.  in  height  and  requires  forms  to  make  the  openings  referred  to. 

In  addition  to  this,  the  wall  in  question  runs  the  entire  length  of 
the  subway,  but  is  omitted  entirely  at  all  stations  for  the  length  of  the 
stations,  doubly  emphasizing  its  failure  to  perform  its  intended  function. 
Even  if  this  were  a  solid  and  continuous  wall,  it  could  not  aid  in  any 


History  and  Remedy 


1!) 


material  sense  the  subway  ventilation,  since  the  so-called  "pistons" 
would  occupy  but  one-half  of  their  respective  cylinders,  and  would 
therefore  only  agitate  the  air  as  Bion  J.  Arnold  originally  pointed  out. 

Street  Grating  Drawbacks 

The  merchants,  hotel  proprietors  and  other  members  of  the  Broad- 
way Association  as  well  as  the  public  at  large  to  say  nothing  of  the 
women  of  the  city  have  made  very  clear  certain  other  fundamental 
objections  solely  from  the  standpoint  of  affecting  trade,  such  as  the 
possible  blowing  of  foul  and  heated  air  in  the  faces  of  intending  pur- 
chasers who  might  gather  in  front  of  the  stores  which  are  to  be  flanked 
by  these  grated  holes  in  the  sidewalk,  etc.  Another  very  obvious 
objection  to  this  scheme  lies  in  the  fact  that  street  sweepings  and  all 
sorts  of  possible  dirt  are  given  entrance  into  the  subway  from  which 
by  every  canon  of  engineering  and  sanitation  these  should  be  rigidly 
excluded.  As  if  all  these  objections  were  not  enough  there  develops  a 
final  objection  so  overwhelming  that  it  is  almost  unbelievable  that  it 
could  have  been  overlooked  by  the  designers,  or  that,  in  not  being 
overlooked,  they  have  disregarded  it.  This  is  nothing  else  than  the 
influx  into  the  subway  of  surface  waters  which  already  have  resulted 
within  a  very  recent  time,  in  four  short  circuits  within  one  day  in  the 
electric  power  which  propels  the  trains.  Even  granting  that  some 
provision  has  been  made  in  the  depths  of  the  subway  to  get  rid  of  such 
surface  water,  why,  it  may  be  asked,  should  intentional  openings  be 
provided  to  admit  the  same?  As  though  all  this  was  not  enough, 
consider  just  for  one  minute  the  problem  of  scavenging  these  open 
sewers  after  they  have  been  in  use  for  any  length  of  time!  That  they 
are  nothing  short  of  open  sewers  is  obvious  to  a  child,  and  an  engineer 
cannot  well  withhold  his  most  drastic  criticism  of  them  on  that  score. 

Contributary  Defects 

We  pass  now  to  a  study  of  Diagram  G,  the  scheme  suggested  by 
Mr.  Henry  G.  Opdycke,  Engineer  for  the  Broadway  Association.  As 
outlined  in  the  press,  and  in  the  public  meetings,  this  contemplates  cut- 
ting great  ducts  through  the  side  walls  of  the  subway  into,  and  through, 
the  basement  of  abutting  properties  at  intervals  along  both  sides  of  the 
subway,  and  then  erecting  on  private  property  great  chimneys  extend- 
ing well  above  the  roofs  of  the  surrounding  buildings  and  discharging 
therefrom  the  contents  of  the  subway  by  means  of  huge  blowers  with 
powerful  electric  motors  placed  at  the  entrance  of  the  ducts  or  the  base 
of  chimneys  referred  to.  Even  granting  that  these  installations  were 
made  midway  between  every  station  and  that  thereby  the  new  subway 
could,  and  would,  be  perfectly  ventilated,  it  is  only  reasonable  to  ask 
how  the  City  could  possibly  secure  the  perpetual  easements  that  would 
be  required  and  pay  for  the  enormous  damages  which  would  result  to 


20 


Subway  Ventilation 


owners  of  private  property?  In  the  judgment  of  at  least  one  of  the 
Rapid  Transit  Official  designers:  "This  plan  would  bankrupt  the  City." 

Without  indulging  in  any  very  elaborate  computations  it  is  evi- 
dent that  each  of  these  ducts  and  chimneys,  even  if  located  between 
each  pair  of  stations,  would  necessarily  have  to  be  probably  not  less 
than  6  feet  internal  diameter  or  in  the  neighborhood  of  8  feet  external 
diameter! 

Any  one  who  has  ever  paid  for  chimneys  of  such  dimensions 
properly  constructed,  say  of  the  height  of  even  a  6  or  8  story  building, 
can  readily  realize  to  what  figure  the  cost  would  run ! 

If  this  scheme  does  nothing  else  than  show  the  desperation  to  which 
the  Broadway  merchants  are  driven  it  is  most  valuable  and  instructive. 

Report  of  Realty  Interests 

Before  passing  to  other  plans  attention  is  called  to  the  action  taken 
by  the  Real  Estate  Board  of  Brokers  who  in  1913  appointed  a  "Special 
Committee  on  Ventilation  of  the  Broadway  Subway"  who  reported  to 
the  Board  of  Governors  on  Jan.  9th,  1914.  The  essence  of  this  is  some- 
what as  follows:  "The  Public  Service  Engineers  suggest  fans  instead 
of  gratings  at  an  estimated  expense  through  capitalizing  the  cost  of 
running  and  the  actual  outlay  at  approximately  $100,000  and  for  plants 
between  stations,  34  in  all,  or  $3,400,000,  but  the  actual  cash  outlay 
for  these  plants  is  not  over  $10,000  each,  not  including  the  cost  of  real 
estate  required  for  the  stack."  In  that  report  it  showed  that  there 
were  provided  between  the  Battery  and  59th  St.,  68  sidewalk  gratings 
approximately  4  ft.  x  200  ft.  long  or  800  square  feet  each,  making  a  total 
of  such  openings  into,  and  out  of,  the  subway  equal  to  54,400  square 
feet. 

If  one  will  make  a  mental  picture  of  these  openings  some  idea  may 
be  had  of  the  extent  of  the  troubles  which  must  ensue  in  the  future  if 
this  scheme  is  adhered  to. 

For  reasons  not  known,  the  agitation  for  improvement  in  the  venti- 
lation of  the  subway  lay  dormant  during  1914  until  it  was  again  started 
up  about  the  close  of  December  when  quite  an  imposing  group  of  Broad- 
way property  owners  again  lodged  a  protest  with  the  Public  Service 
Commission  under  the  guidance  of  Wm.  R.  Willcox,  ex  Chairman  of 
the  Public  Service  Commission.  These  interests  then  presented  the 
ventilating  scheme  set  forth  in  Diagram  H  as  designed  by  Mr.  George 
Hallam  Clark,  formerly  one  of  the  Divisional  Engineers  under  Mr.  G.  S. 
Rice  in  1906,  but  now  no  longer  officially  connected  with  the  Public 
Service  Commission. 

Here  again  we  see  a  most  drastic  scheme  for  solving  the  subway 
problem  consisting,  as  it  does,  of  a  series  of  ducts  superimposed  upon 
the  roof  of  the  subway  with  openings  connecting  into  them  from  the 


History  and  Remedy 


21 


Diagram  H 


subway.  As  publicly  outlined,  these  ducts  were  to  be  joined  together 
at  intervals  along  the  route  of  the  subway  in  such  open  spaces  as  Union 
Square,  Madison  Square,  Herald  Square,  etc.,  and  there  connect  up  to 
chimneys  with  fans  at  their  bases  which  would  probably  exceed  in  size 
the  hugest  employed  even  by  mining  engineers.  If  this  plan  is  for 
psychological  effect  upon  the  city  authorities,  it  probably  is  well  worth 
the  time,  money  and  energy  spent  upon  it,  but  that  it  should  have  the 
serious  endorsement  of  any  body  of  Ventilating  Engineers,  is  beyond 
belief! 


Diagram  I 


22 


Subway  Ventilation 


Again,  granting  that  this  plan  would  efficiently  accomplish  its 
intended  purpose,  it  is  fully  answered  by  the  trenchant  criticism  of  the 
before  mentioned  official  designer  who  calmly  stated  that:  "The  road- 
bed of  the  tracks  would  have  to  be  depressed  by  exactly  the  amount 
required  for  the  superimposed  ducts" — hence  this  plan  also  falls  by  the 
board  because  of  the  enormous  additional  expense  in  time  and  money 
which  would  be  involved  thereby. 

Diagram  I  illustrates  a  condition  which  would  exist  if,  and  when, 
three  partitions  be  erected  as  is  the  case  in  certain  sections  of  the  new 
subways. 

Subway  Dangers  and  Requirements 

The  disaster  which  occurred  in  the  subway  on  Jan.  6th  of  this  year 
with  its  resultant  deaths  and  with  the  asphyxiation  of  several  hundred 
passengers,  crystallized  public  attention  upon  the  subject  of  ventila- 
tion as  probably  nothing  else  could  have  done  and  has  aroused  a  storm 
of  criticisms  from  press,  public  and  engineers  which  it  will  be  hard  to 
still  until  a  final  and  real  solution  is  found  of  the  problem. 

In  passing,  it  may  be  of  interest  to  learn  that  one  writer  to  the 
press  pointed  out  that  in  the  London  tubes  "They  have  put  in  opera- 
tion suitable  air  cleaning  plants,  so  that  80,000,000  cubic  feet  of  air 
charged  with  ozone  is  forced  through  the  tunnel  daily,  75,000  cubic 
feet  of  pure  air  is  forced  through  every  minute  drawing  an  equal  amount 
of  vitiated  air  out."  A  sufficient  answer  may  be  made  right  here  to 
such  a  suggestion  by  stating  that  if,  and  when,  the  subway  is  flushed 
out  so  that  the  contents  are  as  fresh,  and  approximately  as  cool,  as  the 
air  out  of  doors,  the  public  will  undoubtedly  be  well  satisfied. 

It  is  not  sufficient  answer  to  say  that  "only  two  passengers  have 
been  killed  during  the  operation  of  the  subway;"  nor  to  try  and  appraise 
in  money  value  these  lives,  for,  at  any  moment,  a  similar  disaster  may 
occur  and  blot  out,  not  one  or  two,  but  hundreds  of  lives.  Since  there 
is  no  financial  equivalent  for  human  life,  the  only  answer  is:  to  provide 
such  safeguards  in  the  way  of  ventilation  and  security  of  train  opera- 
tion that  no  means  or  method  known  to  engineering  or  science  shall  be 
left  untried. 

As  though  the  fire  was  not  a  sufficient  warning  there  followed  on 
Feb.  2d,  the  four  short  circuits  which  again  tied  up  the  subway  and 
startled,  even  if  they  did  not  endanger,  the  thousands  of  subway  pas- 
sengers. Attention  is  again  called  to  the  fact  that  these  short  circuits 
were  due  to  surface  water  reaching  the  3d  rail  and  power  cables  through 
comparatively  small  openings  which  already  exist  in  the  subway.  What 
then,  we  may  ask,  will  be  the  condition  of  the  new  subways  when  in 
operation  with  holes  in  the  roof  aggregating  54,400  square  feet  to  let 
in  the  dirt,  snow  and  water? 


History  and  Remedy 


23 


It  is  interesting  to  note  that  the  Public  Service  Commission  t  hrough 
its  Chief  Engineer  was  stirred  to  action  by  the  firsl  accident  in  the  sub- 
way and  had  barely  announced  certain  changes  to  be  made  in  the  present 
subway,  in  order  to  make  same  safer  and  more  reliable  in  operation, 
when  the  four  short  circuits  occurred  which  have  just  been  mentioned. 
Proposed  Solution 

If  the  author  had  nothing  more  than  history  and  criticism  to 
present  there  would  be  little  occasion  for  the  publication  of  this  paper. 
Definite  recommendations  and  remedies  for  all  the  ills  that  have  been 
specified  are  however  embodied  in  the  Diagrams  J  and  K  and  are 
hereinafter  elaborated. 

The  essence  of  the  proposed  plan  for  ventilating  the  old  subway, 
or  those  projected,  or,  as  a  matter  of  fact,  for  ventilating  all  such  under- 
ground transportation  tubes  having  a  plurality  of  openings  intermediate 
the  terminals  of  said  subway,  is,  in  fact,  to  cut  up  such  tube  into  short 
lengths  and  ventilate  it,  "piece-meal, "  at  it  were.  It  should  now  be 
quite  evident,  that  this  plan,  or  any  successful  plan,  must  be  predicated 
upon  mechanical,  i.e.,  fan,  ventilation,  assuming,  as  is  the  case,  that 
the  subway  supposed  to  be  ventilated  is  not  a  single-compartment, 
continuous  tube,  with  no  passenger  stations  intermediate  the  two 
terminals.  In  other  words,  if  we  have  a  tube  with  no  apertures  between 
the  ends  and  we  introduce  into  it  a  car  which  practically  fills  the  tube 
and  propel  that  car  through  the  tube,  necessarily  the  car  acts  as  a  piston 
and  we  secure  more  or  less  successful  ventilation  whether  the  tube  be 
vertical  or  horizontal. 

Such  a  condition  practically  does  obtain  in  the  Hudson  tunnels 
and  in  certain  other  subaqueous  tubes,  but  we  may  dismiss  it  from 
consideration  because  such  conditions  do  not  exist  in  the  subways  which  we 
are  considering! 

Now,  having  split  up  our  subway  into  small  sections,  the  second 
essential  requirement  comes  into  play,  viz:  to  absolutely  control  the 
direction,  velocity  and  volume  of  the  inflowing  and  outflowing  air.  Unless 
this  is  done,  it  is  obvious  that  "short  circuits"  will  result  and  all  control 
of  the  ventilation  be  lost!  This  control  can  be  secured  in  many  ways, 
but  the  most  feasible  one  for  the  subways,  as  built  and  projected,  is  to 
install  at  the  various  apertures  in  the  envelope  of  the  subway,  "air- 
lock" doors,  which  permit  free  egress  (or  ingress)  of  passengers  but, 
as  the  name  indicates,  effectually  prevent  all  escape  of  air  save  through 
the  fans. 

Next  comes  into  play  the  trained  judgment  of  the  ventilating 
engineer  to  properly  determine:  the  points  of  ingress  and  egress  for  the 
air;  the  size,  type,  location  and  motive  power  of  the  fans;  and  the  size, 
type,  construction  and  location  of  these  "air-lock"  doors.  From  a 
study  of  the  old  subway  there  seems  to  be  no  question  that:  the  entire 


24 


Subway  Ventilation 


contents  of  the  subway  can  be  exhausted  just  as  many  times  an  hour 
as  is  desirable,  provided  that  sufficient  power  is  supplied  to  the  fans; 
and,  further,  that  this  can  be  done  by  controlling,  say,  every  alternate 
station,  or  rather  pair  of  stations,  at  the  same  general  location  along 
the  axis  of  the  subway.  It  is  obvious  that  all  other  openings  such  as 
the  gratings  provided  in  the  sidewalks,  etc.,  would  necessarily  have  to 
be  closed  so  as  to  avoid  the  " short  circuits"  referred  to,  and  thus 
compel  the  entering  air  to  take  its  intended  course  through  one  set  of 
stations  and  be  exhausted  by  fans  at  the  next  adjacent  pair  of  stations. 
For  further  data  see  Part  II  following. 


PART  II. 


Subway  Ventilation 


PART  II. 

REMEDY 

The  Problem  Defined 

It  must  be  admitted  by  all  who  are  competent  to  speak  thereon 
that  the  problem  of  ventilating  the  subways  of  New  York  is  almost 
wholly  one  of  cooling  the  air  within  them. 

Prof.  Geo.  A.  Soper  in  his  report  upon  the  atmospheric  conditions 
which  existed  in  the  first  subway  in  1905  made  this  clear;  and  Bion  J. 
Arnold  the  great  Chicago  electrical  engineer  and  transportation  expert 
made  this  still  clearer  when  he  declared,  as  the  result  of  his  tests  and 
computations  in  1908,  that  fully  85%  of  all  the  energy  generated  at 
the  power  stations  is  dissipated  in  the  form  of  heat  within  the  subway. 

In  order  to  give  the  layman  an  elementary  illustration  of  just  what 
this  means  Arnold  further  stated  that  this  heat  which  was  thrown  off 
in  the  section  of  the  old  subway  between  the  Battery  and  96th  St.,  was 
equal  to  that  which  would  result  from  burning  inside  the  subway  of 
two  tons  of  coal  at  every  station  every  24  hours  or  more  than  40  tons 
daily. 

Geo.  S.  Rice,  who  wras  chief  engineer  for  the  Rapid  Transit  Rail- 
road Commission  in  1905  which  was  responsible  for  the  design  of  the  old 
subway,  stated  in  his  report  on  the  ventilation  made  to  this  Commis- 
sion in  1906  that  this  excess  heat  and  other  shortcomings  would  be 
cured  by  changing  the  air  in  the  subway  once  every  ten  minutes  or  six 
times  an  hour,  which,  in  the  section  referred  to,  would  be  equivalent  to 
exhausting  approximately  2,700,000  cubic  feet  per  minute,  or  obviously, 
162,000,000  cubic  feet  per  hour. 

Every  one  competent  to  pass  upon  the  subject  of  ventilation 
will  instantly  admit  that  this  subway  standard  set  by  Geo.  S.  Rice  and 
concurred  in  by  Prof.  Geo.  A.  Soper  and  by  Bion  J.  Arnold  is  in  con- 
formity with  the  very  best  practice  in  the  ventilation  of  schools,  hospi- 
tals, theatres  and  other  such  buildings  occupied  by  large  numbers  of 
people  for  considerable  periods  of  time. 

Without  at  this  time,  taking  the  pains  to  prove  that  the  subways 
now  built,  now  building,  or  hereafter  to  be  built,  would  be  ventilated 
to  the  satisfaction  of  the  city,  or  of  the  operators,  or  of  the  public,  even 
if  this  standard  were  fully  carried  out  every  hour  of  every  day  of  the 
year,  it  is  reasonable  to  take  it  for  granted  that,  if  the  subways  are  com- 
pletely flushed  out  from  end  to  end  every  ten  minutes,  the  resultant 
conditions  would  be  tremendously  improved  and  the  present  outcry 
against  the  intolerable  and  dangerous  conditions  which  now  prevail, 
would  be  largely  stilled.    Even  in  1905  Chief  Engineer  Rice  foresaw 


History  and  Remedy 


29 


the  possibility  of,  and  the  dangers  resulting  from,  the  presence  of  fire 
and  smoke  in  the  subway  and  therefore  advised  at  least  an  approxi- 
mation of  this  standard  and  further  actually  installed  some  25  exhaust 
fans  which  (combined)  had  the  capacity  for  sucking  out  of  the  subway 
1 ,000,000  cubic  feet  of  air  every  minute,  or  sufficient  to  change  the  ent  ire 
contents  twice  an  hour. 

The  recent  fire,  loss  of  life,  and  suffocating  of  hundreds  of  pas- 
sengers within  the  subway,  are  the  most  convincing  proofs  that  this 
inevitable  danger  was  clearly  sensed  even  when  a  sufficient  remedy 
therefor  was  not  applied. 

Right  here  is  an  apparent  discrepancy  which,  when  exhaustively 
examined,  explains,  to  a  great  extent,  the  uncomfortable  and  danger- 
ous conditions  which  still  exist. 

"Short  Circuiting" 

If  a  change  of  air  every  thirty  minutes  would  produce  comfortable 
and  safe  conditions  within  the  subway,  and  if  there  are  still  installed 
and  capable  of  instant  operation  powerful  fans  which  are  capable  of 
flushing  out  that  subway  every  thirty  minutes,  then  only  two  conclu- 
sions can  be  reached. 

First,  either  the  fans  are  intentionally  not  operated  at  all,  or 

Second,  when  the  fans  are  operated,  they  are  so  placed  that  even 
though  they  do  literally  exhaust  1,000,000  cubic  feet  of  hot  air  every 
minute,  the  1,000,000  cubic  feet  of  cool  air  (which  must  perforce  bal- 
ance that  exhausted)  is,  in  ventilating  and  engineering  language,  short- 
circuited  and  hence  results  in  no  material  benefit  to  the  subway  as  a 
whole. 

Now,  whether  the  original  25  fans  ever  were  operated  and  tested 
out  at  their  combined  capacity  for  any  considerable  period;  or,  whether 
they  are  capable  of  being  so  operated  today,  even  from  a  source  of 
power  other  than  that  for  train  service  (as  is  absolutely  essential  for 
" safety  first"  reasons),  is  altogether  unimportant,  as  will  be  seen. 

In  order  to  ventilate  the  New  York  subway  (or  for  that  matter  any 
other  structure)  a  comprehensive  plan  or  system  must  be  designed  which 
will  produce  results  (calculated,  and  calculable,  in  advance)  with  the 
same  absolute  certainty  with  which  a  water  pumping  plant  is  installed. 

It  should  be  obvious  to  any  intelligent  person,  however  untechnical, 
that,  if  25  pumps  of  various  sizes  withdraw  water  through  different 
sized  pipes  from  a  common  reservoir  (which  is  to  be  filtered  and  into 
which  the  pumps  again  discharge)  the  water  will  necessarily  flow  to 
each  pump  by  the  shortest  and  easiest  route  and  in  exact  proportion 
to  the  size  of  the  pump  and  the  pipes  which  connect  it  to  the  reservoir. 


30 


Subway  Ventilation 


Air,  in  this  respect  at  least,  acts  exactly  like  water,  hence  it  is  abso- 
lutely necessary  to  know  at  the  very  outset  through  which  inlets  the  air 
will  flow  into  the  subway  (reservoir)  relatively  to  those  outlets  through 
which  the  air  is  to  be  discharged. 

Clearly,  air  must  flow  into  the  subway  through  those  inlets  which 
are  the  nearest  to  any  given  discharge,  or  fan,  outlet,  and  directly  in 
proportion  to  the  number  and  size  of  the  combined  inlets  relatively  to 
this  single  outlet. 

In  other  words,  if  there  be  25  (fan)  outlets  capable  of  discharging 
the  total  (assumed)  1,000,000  cubic  feet  (or  say,  40,000  cubic  feet  each 
per  minute)  at  any  assumed  velocity,  and  if  there  be  250  inlets  (each 
free  to  admit  say,  40,000  cubic  feet  of  air  per  minute  at  the  same  assumed 
velocity)  it  is  self-evident  that  all  the  air  discharged  will  flow  into  the 
subway  only  through  those  25  inlets  which  are  nearest  to  their  respective 
fan  outlets,  and  that  the  entire  remaining  225  inlets  (together  with  the 
sections  of  the  subway  next  adjacent  to  them)  will  be  valueless  for  the 
purposes  of  ventilating  the  subway,  because  of  the  "short-circuiting" 
already  referred  to.  It  is  almost  self-evident  that,  to  prevent  such 
"  short  circuiting,"  all  openings  such  as  existing  or  proposed  gratings 
must  be  permanently  and  completely  closed. 

Necessity  of  Mechanical  Ventilation 

It  might  very  properly  be  asked,  why  are  fans  at  all  necessary  for 
subway  ventilation?    The  answer  is  very  simple  and  is  as  follows : 

It  must  be  admitted  by  every  one,  as  has  already  been  assumed, 
that  to  ventilate  any  structure  (and  certainly  to  ventilate  a  subway) 
its  entire  atmospheric  contents  must  be  removed  and  renewed  with 
fresher,  that  is  cooler,  air  a  given  number  of  times  per  hour  which,  in 
the  case  above,  is  assumed  to  be  two  times.  Now  there  are  but  two 
satisfactory,  really  but  two  known,  methods  of  moving  air,  namely; 
thermally  and  mechanically. 

To  move  large  volumes  of  air  thermally  at  even  a  low  velocity, 
there  must  be  a  very  considerable  difference  in  temperature  between 
the  air  at  the  inlets  and  the  outlets  of  the  assumed  structure. 

The  difference  in  temperature  between  the  air  (even  at  the  roof) 
of  the  subway  and  that  out-of-doors  is  probably  not  more  than  10 
degrees  Fahrenheit  under  the  most  extreme  Summer  conditions  which 
difference  is  utterly  inadequate — as  the  subway  with  its  inlets  and  out- 
lets is  now  constructed — to  produce  any  air  movement  worth  a  moments 
consideration.  Increasing  the  velocity  of  the  air  movement  by  means 
of  chimneys  for  outlets,  even  if  that  were  within  the  realms  of  feasi- 
bility, would  still  be  valueless. 

It  must  be  borne  in  mind  that  the  excess  temperature  in  the  subway 
air  over  that  out-of-doors,  even  though  it  is  actually  but  a  few  degrees 


History  and  Remedy 


Ml 


yet  physiologically  is  comparatively  great,  and,  being  exceedingly 
"uncomfortable"  to  the  average  passenger,  is  at  least  "not  beneficial 
to  health" — Prof.  Soper,  Engineer  Rice,  Expert  Bion  J.  Arnold,  the 
Public  Service  Commission  and  the  Authorities  of  New  York  to  the 
contrary  notwithstanding. 

Need  of  Safety  and  Comfort 

For  ten  years  the  public  has  sensed  the  "discomfort"  but  seemed 
not  to  be  aware  of  the  " danger"  in  the  lack  of  air  movement,  until  the 
recent  disasters  resulting  from  electrical  short-circuits  and  fires. 

Now,  the  psychological  conditions  are  reversed,  and  the  insistent 
demand  is  for  a  "  safety -first "  system  of  ventilation. 

In  short  then,  the  fundamental  requirements  of  subway  ventilation 
are:  " safety"  and  " comfort"  for  the  public. 

To  secure  either  or  both  of  these  requirements  demands  moving 
such  volumes  of  air  as  shall  at  least  meet  the  very  low  standard  quoted 
above,  to  wit:  the  changing  of  the  air  of  the  entire  subway  at  least  twice 
an  hour.  To  accomplish  even  this  is  physically  impossible  by  the 
" thermal-difference "  method,  as  was  abundantly  proven  when  an 
electric  furnace  recently  raised  the  subway  temperature  to  a  metal- 
fusing  point. 

This  reasoning  compels  the  adoption  of  some  " mechanical"  method 
for  moving  the  subway  air. 

"Piston"  Ventilation 

The  attempt  has  been  made  for  ten  years  to  ventilate  the  old  sub- 
way, in  part  at  least,  by  the  so-called  "piston"  action  of  train  move- 
ment and  it  is  planned  to  ventilate  the  new  subways  almost  entirely 
by  the  same  method — which,  it  must  be  admitted,  is  superior  to  the 
inadequate  "thermal"  method  since  it  is  (at  the  least)  "mechanical" 
ventilation.  According  to  the  Engineering  Department  of  the  Public 
Service  Commission  these  "attempts"  to  ventilate  the  existing  subway 
have  cost  upwards  of  $750,000.00. 

This  plan  might  fairly  be  dismissed  with  the  one  comprehensive 
criticism  that  it  becomes  absolutely  inoperative  the  very  instant  train 
propulsion  ceases  for  any  reason,  and,  obviously,  may  so  become  use- 
less at  the  moment  when  most  necessary  for  "safety  first"  reasons — 
as  in  the  event  of  fire  and  smoke  within  the  subway. 

Without  attempting  to  analyze  the  so-called  "piston"  ventilation 
in  all  its  various  forms,  it  is  considered  sufficient  to  admit  that  it  might 
produce  the  assumed  two  air  changes  per  hour,  provided  that:  first, 
each  train  track  should  be  confined  in  a  single  continuous  tube  without 
connection  with  any  other  tube;  and,  second,  that  the  trains  completely 


32 


Subway  Ventilation 


filled  the  tube  in  which  they  ran.  Since  neither  of  these  conditions 
are  met  in  the  old,  or  the  new,  subways  this  " scheme"  should  be  abso- 
lutely disregarded. 

In  passing,  it  might  be  well  to  note  that  in  the  under-water  sections 
of  some  subways — such  as  the  " Hudson  tubes"  where  both  of  the  above 
requirements  are  almost  completely  met — this  so-called  "piston"  action 
has  not  been  relied  upon  to  produce  the  admittedly  very  excellent  venti- 
lating results  which  therein  obtain — but  there  have  been  installed 
in  addition  at  one  terminal  of  these  tubes,  powerful  fans  which  discharge 
the  subway  air  into  a  great  chimney  of  considerable  height. 

Ventilation  Logic 

Attention  is  now  called  to  the  following  fundamental  contentions 
in  regard  to  the  subways  of  New  York  City  as  now  built,  as  now  build- 
ing, or  as  to  be  built: 

(1)  Adequate  mechanical  ventilation  of  any  subway  is  absolutely 
essential  to  safety  and  comfort  of  passengers  and  incidentally  attracts 
traffic  and  insures  profits. 

(2)  Subways  elsewhere  are  adequately  ventilated  by  mechanical, 
that  is,  fan  methods. 

(3)  The  subways  of  New  York  City  never  have  been,  and  are  not 
now,  adequately  ventilated,  either  on  the  score  of  passenger  safety, 
comfort  or  profits. 

(4)  The  subways  of  New  York  City  can  be  adequately  ventilated 
by  means  of  fans  driven  by  electric  motors  taking  current  from  a  source 
of  power  other  than  that  for  train  propulsion. 

(5)  The  problem  of  mechanically  ventilating  all  the  subways  of 
New  York  City  which  now  faces  the  City  authorities,  the  Public  Ser- 
vice Commission,  the  Interborough  Rapid  Transit  Co.,  the  New  York 
Municipal  Railway  Co.  and  the  Public — is  wholly  a  question  of  which 
one  of  the  many  plans  proposed  for  so  ventilating  the  subways  shall  be 
adopted. 

Skeleton  Specification 

The  system  herewith  outlined  is  well  and  fully  comprehended 
under  the  title  of  "sectionalized,"  or  "piece-meal, "  ventilation. 

Primarily  this  system  requires  (in  addition  to  electric  fans  and 
power  cables  which  are  an  inseparable  part  of  any  adequate  mechanical 
system  of  ventilation)  nothing  more  costly  or  complex  than  the  specified 
"air-lock"  doors  and,  either  some  comparatively  slight  additions  to, 
or  alterations  of,  the  subway  ("kiosk")  entrances,  or  the  alternative 
installation  of  light  air-tight  structural  partitions  at  the  station  plat- 
forms. 


History  and  Remedy  33 

All  the  apparatus,  additions  and  changes  would  be  confined  wholly 
to  the  stations  themselves,  and,  at  that,  would  probably  be  installed, 
in  general,  only  at  alternate  pairs  of  stations  along  the  axis  of  the 
subways. 

This  system  neither  contemplates  nor  requires  one  square  foot  of 
property  not  already  an  integral  part  of  the  subway  system  and  is  equally 
applicable  to  any  of  the  subways  now  built,  now  building  or  projected — 
subject  only  to  the  limitations  already  outlined. 

Operation  of  System 

Taking  up  then  this  system  in  its  broad  aspects  it  should  be  readily 
grasped,  even  by  the  layman,  that  if  there  be  installed  at  the  various 
entrances  of  any  given  station,  say  at  18th  St.,  four  electric  fans  (of  the 
proper  size,  type,  and  power  capable  of  exhausting  a  certain  fraction  of 
the  2,700,000  cubic  feet  of  air  per  minute  which  it  is  assumed  would  be 
necessary  to  adequately  ventilate  the  old  subway  between  the  Battery 
and  96th  St.,)  and  if  in  addition  to  the  fans  there  be  installed  at  the 
same  entrances  suitable  " air-locking"  doors  which  would  permit  free 
ingress  and  egress  of  passengers  but  no  ingress  or  egress  of  air — then  it 
must  necessarily  follow  that  for  every  cubic  foot  of  the  subway  contents 
discharged  by  these  fans  at  18th  St.  an  amount  exactly  equal  thereto  must 
flow  into  the  subway  from  the  next  adjacent  openings.  In  the  case 
taken,  approximately  half  of  the  fresh  air  would  enter  at  the  14th  St. 
station  and  the  other  half  would  be  drawn  in  at  23d  St. 

As  already  noted,  all  sidewalk  gratings  and  other  such  intentional 
or  chance  openings  would,  naturally,  be  sealed  or  otherwise  done  away 
with. 

Now  if  there  were  a  total  of  twenty  such  installations  between  the 
Battery  and  96th  St.  there  would  be  needed,  say,  one  hundred  such  fans 
to  exhaust  the  total  required  2,700,000  cubic  feet  of  air  per  minute. 

If  these  fans  averaged  54  inches  in  diameter  and  consumed  even 
10  horse  power  each,  there  would  be  required  a  total  of  1000  horse  power 
hourly  to  adequately  ventilate  the  entire  assumed  subway. 

If  operated  even  20  hours  daily  for  200  days  in  the  year,  and  if  the 
cost  of  electricity  be  taken  at  one  cent  per  horse-power-hour,  the  total 
annual  cost  would  be  but  $40,000.00 — certainly  a  small  insurance  upon 
the  lives,  health,  comfort  and  efficiency  of  the  subway  patrons  and 
employees ! 

If  instead  of  the  assumed  standard  of  ventilation  it  is  necessary  or 
desirable  to  change  the  air  more  frequently  or  less  frequently,  or,  to 
ventilate  a  subway  having  cubic  contents  ten  fold  that  of  the  assumed 
subway — it  is  necessary  to  inform  only  the  layman  that  the  comparative 


34 


Subway  Ventilation 


cost  of  operation  (as  between  any  two  or  more  systems  which  will  secure 
like  results)  will  not  vary  enough  to  constitute  a  merit  or  a  demerit  to 
one  or  the  other. 

Comparative  Merits 

The  foregoing  should  now  be  sufficient  to  make  it  clear  that  the 
comparative  advantages  of  any  proposed  and  adequate  system  may  be 
resolved  into  such  questions  as:  ease  and  simplicity  of  installation; 
initial  cost;  interest  charges;  maintenance;  depreciation;  ease  of  exten- 
sion or  modification;  appearance,  etc.  Assuming  that  only  wholly 
adequate  systems  are  being  compared  and  that  all  are  practically  on  a 
parity  on  such  scores  as:  operating  cost,  durability,  manipulation,  ini- 
tial cost  of  fans,  motors  and  electric  cables — all  further  consideration 
of  this  "sectionalized"  or  "piece-meal"  system  of  subway  ventilation 
may  be  confined  to  the  very  practical  questions  of :  structural  changes 
or  additions  to  the  subway  and  abutting  property ;  and  to  the  time  and 
manner  of  installation  and  completion. 

To  begin  with,  as  has  already  been  pointed  out,  all  work  required 
for  the  installation  of  this  system  is  absolutely  limited  to  the  stations, 
and  to  approximately  only  half  of  them  at  that.  No  work  whatsoever 
need  be  done  in  the  portions  occupied  by  the  tracks,  hence  train  move- 
ments could  not  possibly  be  affected  either  by  the  installation  or  oper- 
ating of,  or  addition  to,  this  system. 

Methods  of  Installation 

It  will  be  noted  by  an  examination  of  the  explanatory  diagrams 
that  either  of  two  broad  methods  may  be  followed  for  the  installations 
at  the  stations — the  purpose  and  result  of  which  is  to  absolutely  insure 
against  all  "short  circuiting"  of  air  movement  and  to  guarantee  con- 
trol over  the  direction,  velocity  and  volume  of  the  air  moved  by  the 
fans  so  that  the  results  calculated  in  advance  of  installation  shall  actually 
take  place  when  the  equipment  is  operated. 

The  first  of  these  two  methods,  and  the  preferable  one,  is  to  install 
the  "air-lock"  doors  at  the  entrance  of  the  "kiosks"  with  the  fans  in 
the  "kiosk"  cowls  whence  they  would  discharge  through  louvres  as 
shown  in  the  right  halves  of  Diagrams  J  and  K. 

The  second  method  is  to  erect  suitable  simple  air-locking  "bulk- 
heads" or  partitions  at  the  station  platforms,  say  taking  the  place  of 
the  railing,  etc.,  on  the  line  of  the  ticket  choppers  stand.  In  this  par- 
tition would  be  installed  the  specified  "air-lock"  doors,  while  the  fans 
might  also  be  installed  in  this  same  "bulkhead"  partition,  or  could  be 
located  at  any  convenient  point  beyond  and  be  connected  to  the  parti- 
tion by  suitable  ducts.    See  left  halves  of  diagrams. 


History  and  Remedy 


35 


A  very  little  study  of  this  system  will  make  it  evident  that  if,  and 
when,  it  is  desirable  so  to  do,  any  number  of  stations  may  be  "  air- 
locked"  and  the  fans  omitted  thereat,  provided  that  due  provision  is 
made  at  the  first  adjacent  "fan  station"  to  handle  the  proportion  of 
the  air  discharged  which  should  have  been  taken  care  of  at  the  station 
so  "air-locked." 

It  should  now  be  clear  that  the  secret,  so  to  speak,  of  this  system 
and  the  essential  feature  (which  differentiates  it  from  all  others  hereto- 
fore tried  or  now  being  proposed)  is  the  scientific  employment  and  loca- 
tion of  these  "air-locking  "  doors  constituting  as  they  do  elementary 
simple  ventilating  tools  of  proven  worth,  and  which,  on  the  very  face 
of  it,  guarantee  control  of  the  predetermined  movement  of  the  air  and 
hence  insure  success. 

Initial  Cost 

One  of  the  greatest  gains  which  would  result  from  an  adoption  of 
this  system  would  lie  in  the  possibility  of  immediately  stopping  all  the 
costly  construction  required  for  the  proposed  "piston"  system  of  venti- 
lation now  being  carried  out  in  the  new  subways. 

As  has  already  been  shown  this  so-called  "piston"  system  is  totally 
inadequate  for  safe  and  comfortable  subway  ventilation  regardless  of 
whether  its  cost  is  one  dollar  or  several  millions  of  dollars — as  is  probably 
the  case. 

Even  a  cursory  examination  of  the  plans,  specifications  and  actual 
construction  of  the  new  subways  as  now  under  way  is  sufficient  to  prove 
this  contention. 

In  passing  it  may  not  be  amiss  to  point  out  that,  to  provide  for  this 
"piston"  system,  there  is  to  be  built  in  the  middle  of  the  subways, 
separating  the  uptown  from  the  downtown  tracks,  a  concrete  wall 
some  ten  inches  thick  and  thirteen  feet  high  with  large  apertures  formed 
therein  every  ten  feet  for  free  "safety"  passages  for  the  employees,  and 
possibly  for  the  passengers,  from  one  side  of  the  subway  to  the  other. 
This  partition  is  to  be  omitted  altogether  at  all  stations  and  since  each 
train  occupies  but  one-half  the  cross  section  of  the  "tube"  in  which  it 
runs,  and  since  the  central  partition  is  but  a  huge  "grating,"  "short 
circuiting"  of  the  air  is  inevitable,  hence  this  wall  can,  by  no  stretch 
of  the  imagination,  fulfill  the  purpose  for  which  it  is  intended! 

In  addition  to  this  concrete  wall  there  is  incorporated  in  the  designs 
and  construction,  the  system  of  great  concrete  ducts  paralleling  the  sub- 
way on  both  sides  which,  at  the  bottom,  open  into  the  subway,  and  at 
the  top  open  onto  the  sidewalk  through  the  iron  gratings  to  which  the 
public  in  general,  and  the  Broadway  merchants  and  realty  interests  so 
seriously  object. 


36 


Subway  Ventilation 


It  might  almost  be  said  that  the  new  subways  are  built  around 
the  system  of  " piston"  ventilation,  instead  of  including  a  system  of 
ventilation  in  the  subway  construction! 

These  ducts  must  prove  in  use  to  be  little  else  than  open  sewers 
incapable  of  being  flushed  out,  and  in  addition  must  admit  surface 
waters  into  the  bowels  of  the  subway,  with  the  extreme  liability  of 
causing  costly  and  dangerous  " short-circuits"  to  the  power  cables 
serving  train  propulsion,  as  occurred,  recently  four  times  in  one  day! 

Contributary  Gains 

All  the  time,  skill,  labor,  materials,  defects  and  dangers  involved 
in  these  constructions  necessary  for  the  " piston  system"  may  be  wholly 
saved  by  the  adoption  of  the  proposed  "fan  and  air-lock"  system! 

In  addition  to  these  savings  the  "air  locking,"  "piece-meal" 
system  may  be  installed  at  any  time,  and  in  the  minimum  time,  with- 
out even  retarding  a  train  or  a  passenger. 

Since  there  is  nothing  whatsoever  experimental  about  this  system, 
and  since  all  the  results  can  be  calculated  in  advance,  and  since  its  cost 
is  certainly  much  below  any  plan  suggested,  it  should  apparently  appeal 
to  the  City,  the  operators  and  the  public. 

On  the  ground  of  a  "  safety-first "  system  alone  the  method  proposed 
seems  to  meet  every  requirement  for  quickly  exhausting  any  smoke 
which  might  possibly  be  produced  in  the  subways. 

That  the  proposed  system  is  a  "  safety -first "  system,  as  well  as 
adequate  on  the  score  of  health,  is  almost  self-evident  when  it  is  realized 
that,  even  if  it  were  idle  at  the  time  of  a  fire,  a  single  master  electric 
switch  at  the  power  house  could  be  instantly  thrown  into  action,  auto- 
matically or  manually,  thereby  starting  every  fan  at  maximum  capacity. 
This  would  insure,  as  has  already  been  shown,  the  flushing  out  of  "the 
entire  cubic  contents  of  the  subway  in  ten  minutes!^  Incidentally  the 
smoke,  because  it  is  heated,  would  naturally  rise  first  to  the  roof  of  the 
subway  and  it  is  from  this  level  that  the  fans  would  always  be  drawing 
the  strongest. 

Summary  of  Advantages 

The  advantages  of  this  "sectionalized,"  "air-locking,"  system  of 
electric-fan  subway  ventilation  may  be  summed  up  as  follows: 

(1)  Is  calculable  and  results  can  be  guaranteed  in  advance  of 
installation. 

(2)  Is  absolute  in  results  sought. 

(3)  Is  independent  of  all  train  movement. 


History  and  Remedy  ^7 

(4)  Is  controllable  as  to  results  secured  to  correspond  to  hourly, 
daily  or  seasonal  demands. 

(5)  Is  positive  since  "  sectionalized "  into  multiple  units  insuring 
against  crippling  of  system  by  failure  even  of  several  motors  at  the 
same  time. 

(())  Is  economical  in  installation  and  maintenance  costs. 

(7)  Is  efficient  in  operation  since  employing  only  apparatus  espe- 
cially developed  for  its  intended  purpose. 

(8)  Is  cheap  to  operate  since  all  cost  rates  are  at  the  minimum. 

(9)  Is  an  insurance  on  lives,  comfort,  health  and  efficiency  of  pas- 
sengers and  employees. 

(10)  Is  available  for  all  subways. 

(11)  Is  harmonious  in  appearance. 

(12)  Is  hygienic  since  unaffected  by  street  conditions. 

(13)  Is  weatherproof  since  devoid  of  street  openings. 

(14)  Is  alterable  to  suit  changing  conditions. 

(15)  Is  simple  to  operate. 

(16)  Is  rugged  in  use. 

(17)  Is  a  " safety  first"  and  an  "emergency"  system  being  operable 
instantly  from  an  idle  state. 

(18)  Is  divisible  to  meet  all  requirements  of  subway  design  and 
operation. 

(19)  Is  a  final  solution  of  the  public's  demands,  the  City's  experi- 
ments, and  the  operator's  obligations,  throughout  the  ten  years  of  plan- 
ning, building  and  operating  the  subways  of  New  York  City,  which, 
when  completed  will,  it  is  estimated: 

Comprise  more  than  240  miles  of  track,  and  will  have 

Cost  more  than  $250,000,000  and  will 

Carry  more  than  2,000,000,000  passengers  per  Annum. 


38 


Subway  Ventilation 


History  and  Remedy 


39 


1*1 1 


